Compressor



- 30 same assignee as the present application.

Patented Nov. 27, 1928.

warren STATES A 1,693,323 PATENT ol-"FIcE.

CHRISTIAN STEENSTRUP, OF SCHENECTAD'Y. NEW YORKQASSIGNOR TO GENERALELEC- TRIO COMPANY, A. CORPORATION OF NEW YORK.

COMPRESSOR.

Application filed April 27.

My invention relates to compressors of the piston and cylinder type andparticularly to compressors adapted for compressing the refrigerant indomestic refrigerating machines. An object of my invention isthe provision of a compressor having an improved construction which among otherdesirable characteristics shall be efficient, quiet in operation, andeasily manufactured.

My invention will .be better understood from the following descriptiontaken in connection with the accompanying drawing, and its scope will bepointed out in the appended claims.

Referring to the drawing, Fig. 1 shows in cross section a compressorinvolving my invention; Fig. 2 is a section approximately on the line2-2 of Fig. 1, and Fig. 3 shows a detail of the compressor drawn to alarger w scale.

While the compressor involving my invention is not limited to anyparticular use, I have constructed itand also illustrated it herein as apart ofan'electric refrigerating machine of the type especially adaptedfor domestic use, such being shown for example in my copendingapplication, Serial No. 166,212, filed Feb. 5, 1927 and assigned to theA com ressor insucha machine need have but smal capacity, neverthelessit must be efiicient to insure economical operation, must run quietlyand must be simple to manufacture. These requirements I havesuccessfully attained in the construction now to be described.

In Fig. 1, the frame 1 has journalled therein the vertical shaft 2 tothe upper end of which is secured the rotor 3 of the driving motor andat the lower end of which is formed the wrist'pin 4. The oscillatingcyliuder 6 has trunnions 7 and 8 by which it is pivotally mountedrespectively in the frame 1 and bottom plate 9. Hollow piston 10 has thebearing 11 for the wrist pin 4 whereby the piston is reciprocated andthe cylinder is osciliated. Inlet passage 13 communicates when thecylinder is in proper. angular position with the intake port 14 locatednear the end of the cylinder bore. The exhaust valve comps the disk 16which engages the end of the der as a seat and from which it is'adaptobe lifted bodily when the compressed gas is discharged into the space 17sit) 1927. Serial No. 187.069.

from which it escapes through passages not shown. For quiet operation athigh speed the valve disk 16 should be light in weight, therefore thin.For the valve to be tight the disk must also have a seat engagingportion which is flat to such a degree that it makes continuous contactwith the seat and should not be deflected by the differences inpressures which may exist on opposite sides there of. I have found thata construction which meets these conditions in avery satisfactory mannerand which may be easily manufactured comprises a metal disk having asubstantially flat outer portion for engaging the bowed body portion.Lapping or other fin- I ishing of such a valve disk toobtain uniformcontact around the valve seat I have found to be unnecessary. By havingthe body of the valve disk concavo-convex, preferably arranged with theconvex face inwardly, the disk is better able to withstand withoutdeflection the relatively large pressure diiferences which obtain onopposite sides thereof during the suction stroke. In order to preserve avery small clearance with such a valve I make the end face 18 of thepiston 10 concave with substantially the same curva- 90 y ture as thebody of the valve disk.

The end of the cylinder 6 with the valve disk 16 is covered by the endhead 20 which is constructed to constitute a mufiler. Being preferably suare in shape it is shown secured 5 to the cylin er at the corners byscrews. 21. Small openings 22 in the-sides allow the escape of thecompressed gas into the space 17 in the frame, and the gas is dischargedfrom this chamber in two successive stages under the control of ports 27formed in' the inside of the cylindrical wall of the casing 1 and valvefaces 28 on the body of the compressor cylinder 6 between whichexpansion pockets 29 are formed. Such an arrangement of expensionpockets is more fully described and claimed in my application, SerialNo. 278,589, filed May 17 1928. 5 For resiliently holding the valve diskon the seat and for cushioning the outward 11o movement thereof, I haveprovided a thin normally flat disk 24 preferably of spring steel betweenthe valve disk and the mufller 20. Spring disk 24 is given an initialtension when the parts are assembled by causing the disk to be slightlydeflected by engagement movement of the valve disk under the restraintof the central portion of the spring disk for the escape of thecompressed gas. After the valve disk has moved a predetermineddistance,however, further movement is met by the additional resistanceeffected by the peripheral portion of the spring disk engaging themuffler. Continued outward movement of the valve disk now is opposed bya greater force than before for the spring disk is required to bend onthe short radius represented by the radial dis,- tance between itsperiphery and its point of contact with .the valve disk. This cushioningeffect of the spring disk tends to bring the valve disk to rest quicklyand noiselessly; the valve disk nevertheless is returned to its seatunder the force of a relatively light spring which also tends towardquiet operation. At the center of the muffler I have shown a smallopening 26 to assist in equalizing the pressure on the two sides of thespring disk.

What I claim as new and desire to secure by Letters Patent of the'UnitedStates, is

1. A compressor comprising a cylinder, a

piston therein, an exhaust valve for the cylinder comprising a thinrigid disk seating against the end of the cylinder, said diskhavresilient disk between said end head and said rigid disk.

2. A compressor comprising a cylinder, 9.

disk at spaced points. and when deflected a predetermined amount by saidvalve disk to engage the end head at another point spaced from saidfirst mentioned points.

' 3; A compressor comprising a cylinder, a

piston therein, an exhaust valve disk seating against the end of thecylinder, an end head for the cylinder and means for yieldingly opposingand cushioning outward movement of the valve disk comprising a resilientdisk arranged normally to engage the valve disk and an end headrespectively at portions adjacent its periphery and its center and whendeflected a predetermined amount to engage the end head also at itsperiphery.

4. A compressor comprising a cylinder, a piston therein, a rigid valvedisk having an inwardly concaved body portionand an outer substantiallyfiat portion seating against the end of the cylinder, a muffler coveringthe end of the cylinder having a central inward projec- 'tion thereon,and a disk spring engaging said projection at its central portion andsaid valve disk at its outer portion, said disk spring being adapted toengage said m ufiier at its periphery when deflected a amount by thevalve disk.

5. In a refrigerating machine a compressor comprising an oscillatablymounted cylinder, a piston therein, a muffler secured to the end of thecylinder having a plurality of small discharge openings in itssidewalls, a rigid valve disk having a concavo-co'nvex body portion anda substantially flat edge portion engaging the end of the cylinder and aspring disk between the valve disk and the mufiler.

In witness whereof, I have hereunto set mv hand this 26th day of April,1927.

oHmsTIAN srnnnsrnnr predetermined CERTIFICATE OF CORRECTION.

Patent No. L693, 323. Granted November 27, 1928, to

CHRISTIAN STEENSTRUP.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 2,line 43, claim 1, for the word "fixed" read "flexedf; and that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case inthe Patent Office.

Signed and sealed this 8th day of January, A. D. 1929.

M. J. Moore, (Seal) Acting Commissioner of Patents.

